


Via Purifico

by angelic_ly



Category: Kingdom Hearts
Genre: (at least I like to consider it as much), Canon Compliant, Gen, KH3 prediction, Kingdom Hearts 3, it's one very long battle fic with a happy ending, my take on how I think Terra's gonna get saved
Language: English
Status: Completed
Published: 2018-12-23
Updated: 2018-12-23
Packaged: 2019-09-25 15:29:17
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,600
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17123957
Author URL: https://archiveofourown.org/users/angelic_ly/pseuds/angelic_ly
Summary: I wanted you to face the darkness, because you're the one who can.“I know you’re in there, Terra!” He calls out, raising his Keyblade and pointing it at Xehanort, “I’ll get your heart back -- I’ll set you free!”In your hand, take this key.





	Via Purifico

**Author's Note:**

> Music Inspiration: Via Purifico (FFX, the original version), Project Destati: DARKNESS (the whole album)
> 
> This is me trying my hand at "action/battle writing" again, since the last time I wrote this kind of thing was... maybe four or five years ago. I'm pretty happy with how it turned out!

Riku has been here before. Not this exact location, no, but this darkness. He’s been here before. This is Ansem’s -- no, _Xehanort’s_ darkness, and previously he hoped he’d never have to come into contact with it again.

(Of course, it stood to reason that he was one of the few eligible to face this darkness, because he’d been haunted by it for so long, because he fought it for so long, because he overcame it, because he “developed a certain resistance” to it. So, of course, it was only reasonable to assume that he’d probably be the one to dive back in. He didn’t expect any less of fate, but he hoped otherwise.

Then again, he wouldn’t wish this burden on anyone else, especially if he had the best chance of success. It wouldn’t be the first time he’s had to drive the darkness out of a heart, and it surely won’t be the last. This is part of the duties that fall upon the shoulders of those who claim the title of “Master,” and he won’t hesitate to complete it.

Xehanort's heart was no stronger than his own, he supposed.)

Riku stands, viscous darkness sticking to the soles of his shoes. He wants to shake it off, but he knows it’ll have no effect; the darkness is everywhere, thick and pressing in on all sides, so it would be no use. His Keyblade comes to his hand unbidden, responding to the anxiety that he’s been trying to push down and ignore. His heart still yearns slightly for the broken Way to the Dawn, and he pushes that down, too.

He stands, and he waits. The darkness dances around him, flickering around the edges of his vision as if trying to form a pseudo-light. Riku stares down at the pillar beneath his feet, and he notices that it’s not perfectly circular. It’s got more of an oval shape, and it pinches slightly in the middle. He can’t begin to assign a meaning to it before the darkness pulses, and he suddenly becomes aware--

Someone is with him.

While he knew coming in that solving this diplomatically was not an option, he still doesn’t raise his Keyblade quite yet. He waits. Riku wants to know exactly what he’s facing.

He’s not disappointed. The already-imposing form of the Dark Guardian towers over the pillar, much larger than he’s ever seen it before. He’s reminded of a Darkside, and he feels that it’s the only way to properly compare the sheer scale. When he looks down, his gaze meets one of molten gold, and he knows immediately that this is Xehanort.

Xehanort doesn’t look the same. This isn’t his younger self, it’s not the Heartless or Nobody version of himself, it’s certainly not one of the other thirteen Seekers, and it’s not his true self. This Xehanort has the same sinister glare, the same crooked smile, but he’s different -- familiar in a way that tugs on Riku’s heartstrings.

Xehanort’s darkness is familiar, yes, but this is a different memory.

Realization strikes him, and he keeps it off of his face, though he can’t stop the instinctive tensing of his body. At first, Riku had a face to match the memory with. He knew the man was all earth tones, a gentle smile, a smooth yet rumbling voice, and a Keyblade with the weight of a mountain. Then, Riku got a name to attach to it -- the name of a friend who was lost, and who needed to be brought back. Now, he’s hit with the pain of seeing this face from his childhood distorted by the darkness.

This is Terra. His body is occupied -- trapped -- by Xehanort. _This_ is who he’s supposed to save.

Xehanort summons his Keyblade -- no, he summons two. In his right hand, he has his own, that favored blade of darkness. In his left hand, he has the Keyblade that strikes a nerve in Riku, the blade whose hilt he had touched so long ago. That is not his Keyblade, yet still he wields it. Riku raises his own in response.

Riku notices Xehanort widening his stance, preparing for an attack, and he notices that the darkness does not ripple in response. Just like Ansem always did, Xehanort bends the rules of gravity to turn the tides in his favor. If there’s one thing to thank Ansem for, it’s for giving him experience in fighting this kind of opponent.

Xehanort sneers, grip tightening on his weapons. “You really think you can win, boy?”

Riku can’t stop his response to the taunt. “Wouldn’t be here if I didn’t.”

That’s all the conversation he gets. At the same time that Xehanort lunges at him, he catches the movement of the absolutely massive Dark Guardian. Somehow, Riku knows that using his darkness to aid his speed won’t help him in this fight, so he leaps into a handspring just in time to avoid both of their attacks. The pillar rumbles against the force of the Guardian’s hand slamming down on it, but it doesn’t shatter. Riku isn’t worried; he knows the heart is stronger than that.

He barely lands completely on his feet before Xehanort is rushing him again. This -- this is different. Ansem always attacked from a distance, but Xehanort has the luxury of two Keyblades and of doing battle inside his own heart. Xehanort can bend the rules, and in here, Riku is the intruder.

Riku ducks to the left and jabs forward, trying to get a hit in. Xehanort slides out of range, then returns just as ferociously as before. Riku dodges with all his effort, though he knows he can’t continue like this. In here, a battle of endurance won’t end well. He’s got to win through power or speed or even both -- but not endurance.

Riku sorely wants to call upon his own darkness -- it always made things easier. He blocks a direct hit from both of Xehanort’s Keyblades at once, and he grits his teeth against the force behind it. His left wrist throbs in protest, but he pushes through the pain. The Guardian moves to attack again, so Riku maneuvers himself from the gridlock and keeps moving. Even if the Guardian moves deceptively quickly for its size, it can’t keep a solid grip on a target constantly in motion, which is exactly what Riku intends to be.

At the forefront of his mind, the battle rages on, and he sinks into his training practices, falling into the steps he’d learned and the steps he taught. In the background, he remembers said training, awkwardly instructing and slowly gaining confidence as his students did, with him learning just as much as them. He remembers stepping to the side and letting the more senior Master take over lessons--

_Aqua. Master Aqua._

The darkness is sticking to his shoes, and Riku knows that he’d be able to move faster if he didn’t have to worry about his sneaker sliding off of his foot. If only he had his Dream Eaters, he could easily lift into _Rising Wing_ ; with the boost in his abilities that it provided him, he’d stand a better chance at victory.

But this isn’t Sora’s heart, and Riku is alone.

Riku missteps and the Guardian catches him with a glancing blow -- though can he really call it that, when the attack effortlessly sends him airborne? Riku braces himself for impact and waits. He’s not worried about falling over the edge of the pillar. In a heart, it’s different, it’s weird -- the space around you seems to move more than you do. The pillar stays, and the space moves. He’s sure it’s distorted itself now, because the way he skids to the edge indicates that he would have gone sailing over it in any other setting.

Riku is quick to rise to his feet, all for the better since Xehanort is upon him again. He ducks out of the way of a horizontal swipe and slashes up and out to counter the attack. Even though it connects, Xehanort doesn’t seem fazed at all, and immediately Riku knows he needs to come up with a better plan than just attacking when possible. He can’t win on endurance, he has to find another way.

Hastily, he calls on the magic inside him and throws out a Firaga spell. It narrowly misses Xehanort, but it achieves its intended purpose and gives Riku just a second’s more time to think, a second’s more time to put some space between him and Xehanort. He needs to come up with a plan, he’s gotta win this, too much is riding on this one victory--

Xehanort cloaks himself in darkness and rushes forward, and Riku can barely dodge. The Guardian tries to catch him with another swing, but Riku leaps back and launches another fireball at the offending hand. The Guardian roars in response, shaking its smoking hand, and the pillar shudders underneath him.

Riku loses his footing, stumbles, falls to one knee -- he looks up in time to see the downward swing of Xehanort’s Keyblade, a strike meant to incapacitate, if not finish him -- the Dark Barrier comes up on instinct. Riku doesn’t think about it. The dome glitters brightly as it takes the impact of Xehanort’s strike.

Everything goes black.

His Keyblade disappears, but there’s no flash of light. Riku claws at his chest with his hands, only barely able to stay upright on his knees. He can’t breathe, he can’t breathe he can’t breathe he can’t **breathe** \--

“It was foolish to try and pit your darkness against mine, boy. We both know whose is superior.”

Xehanort sounds like he’s won. With the way that Riku’s chest pounds, that the excruciating pain completely immobilizes him, that the darkness presses in, piercing and crushing his heart, maybe he has. Riku lets out a choked cry for every blow Xehanort gives in his efforts to shatter the barrier -- it feels like every strike is lancing directly through his brain.

The darkness coating the pillar writhes underneath him and starts to creep up his body, wrapping itself around him and trying to consume him in its cold embrace. It feels just as slimy as he remembers, but even the thought of attempting to shake it off right now is incredibly overwhelming.

This darkness, it might--

_“But what if his darkness overtakes you?”_

_“If that happens, then the darkness will show me the way.”_

_She smiles. She looks almost… relieved. “Yes… that’s true.”_

No. Riku has been here before. Riku knows this darkness. This is the darkness Xehanort infected him with so long ago, this is the darkness that he turned into his own, and this is the darkness he became resistant to. This is the rawest form of one of his power sources; this is Riku’s darkness as much as it is Xehanort’s, now. And Riku?

Riku knows how to handle his own darkness.

_“You’ve gotta just remember to be brave. Know that the darkness is there and don’t give in. If you do that, you will gain strength -- the kind that’s unlike any other. You’ll be able to escape the deepest darkness--”_

She was right.

The pain in his chest doesn’t subside, he doesn’t think, but he controls it and forces his body to move nonetheless. The darkness melts off of him and his Keyblade comes back to his hand. When Riku stands, the barrier shatters outward, knocking Xehanort back. Riku clenches his hand against his chest, sweat beading on his brow, then throws himself into his battle stance.

It’s difficult to take darkness as wild and unruly and overwhelming as Xehanort’s and turn it back against him. It’s risky. The sheer amount of power in this darkness feels like it’s corroding his heart, but he won’t -- _can’t_ \-- lose to this.

“Maybe your darkness is superior, but it’s the same as mine, and I have something you don’t -- the light.” Riku grits his teeth against the pain wracking his body and dashes forward, clashing blades with Xehanort. “My friends are waiting for me, and they’ll lend me their strength.” He shoves his weapon forward, and Xehanort finally staggers.

He seethes, locking Keyblades with Riku again, glaring into his eyes. “What good will they do for you? They can’t help you here, not while you’re consumed by the darkness.”

Riku can’t help but grin, even as he can feel himself getting exhausted. “They don’t have to be here. They’re in my heart -- _they_ are my power!” The gelatinous darkness that used to stick to his shoes and burden him now pushes up against his feet, like a spring loaded in every step he takes. “Sora and Kairi are relying on me to come back safely. Mickey and the others are relying on me to defeat you.” He matches Xehanort blow for blow. “Ventus and Master Aqua are relying on me to bring him back.”

Xehanort staggers again, though Riku knows it’s not his own doing -- already the darkness is beginning to resist him, and even to him his attacks are starting to feel weaker. Still, something is affecting Xehanort, and Riku’s going to try to use it to his advantage.

“I know you’re in there, Terra!” He calls out, raising his Keyblade and pointing it at Xehanort, “I’ll get your heart back -- _I’ll set you free!_ ”

The darkness thins slightly, and Xehanort is covered in an aura the color of sunset. Riku can finally breathe a little bit easier, and he takes full advantage of this as he stays on his guard. There’s a flash, and Xehanort’s left hand is empty. He scoffs at it, scowling.

“It’s been a long while since you fought like this, Terra.” He spits the name as if it’s acid on his tongue. “No matter.” Xehanort turns his fiery gaze onto Riku, a new determination alight in his golden eyes. “I don’t need your help to defeat this boy.”

They clash blades again. Their forces are, for now, equally matched. For every inch one gains, the other quickly takes it back. Riku plants his feet and pushes harder, but Xehanort doesn’t give -- in fact, he smirks. Riku hears the whir of the giant open palm cutting through the air just before it smacks into him, again sending him airborne.

But things are different this time.

Riku twists in the air and allows the darkness to surge up and meet him as he makes his landing. Though his legs ache from the sheer impact of it, he pushes off the darkness and dashes at the Guardian. He launches a fireball in advance of his attack, and it explodes upon impact. The Guardian roars and the pillar shakes again, but Riku isn’t fazed. A giant fist swings down at him and he rolls to the side to avoid it, then leaps into the air, landing on top of it. The Guardian rears back to shake him off, and he uses the momentum to send himself soaring.

Riku spins himself around, spiraling in midair, and yanks on the darkness inside of him, calling upon its power. He yanks on his own magic, setting his weapon ablaze with dark flames. He roars out a battle cry and descends on the Guardian, his attack spinning directly through it.

Riku lands on his feet with a flourish, chest heaving. The pillar lurches as the Guardian screeches and claws at its face, but the darkness clings to Riku, keeping him in place. He watches tiredly as the Guardian explodes into a dark cloud, its final roar echoing as it disappears.

The darkness thins more, and Riku stumbles before turning to face Xehanort again. He swings his Keyblade around and up, again falling into his battle stance. Xehanort glares at him, raising his own blade. “One on one, then,” he says, and charges forward.

They trade blows. Riku grits his teeth against the assault, all of his effort going into just keeping up. The adrenaline rushing through his veins isn’t enough to stave off the ache of his body or the throbbing in his heart. Even if the thinning darkness is weakening Xehanort, it’s weakening Riku, too. He can’t draw nearly as much power from the dwindling source -- before long, he’ll have exhausted himself, if he hasn’t already.

He’s back at square one, in a way. Still needs a plan, still needs a way to keep the tides in his favor.

He considers the idea of using the light within him to fight, but even with his grip on the darkness loosening, going from one extreme to the other is risky -- riskier than just continuing to wear down Xehanort’s darkness. Brighter lights create deeper shadows, anyway, and he can’t risk his opponent getting even the slightest upper hand. Riku scowls and drives himself back into battle, wishing he had more options that weren’t so dangerous.

Now that he doesn’t have to worry about the Dark Guardian, Riku can finally fully focus his attention on Xehanort. He notices -- belatedly, probably -- that what’s left of the darkness is rippling in response to Xehanort’s movements. He’s slower because he’s no longer able to alter gravity to his advantage, but he makes up for it in sheer brutality.

Riku lunges forward, Keyblade thrust out. He misses his mark, but the attack still connects elsewhere; Xehanort stumbles over his retaliation, but Riku is still sent reeling by the impact of the Keyblade colliding with his side. He manages a single leap back to put some distance between them, but upon landing his knees buckle underneath him. He catches himself before he topples over completely, but he can’t find the energy to stand again.

Xehanort laughs, and even though it wheezes it’s still mocking. “Giving up already? I thought you were stronger than _that_.”

“That’s my line,” Riku breathes out, digging his Keyblade into the pillar and using it to get the leverage he needs to stand. “I told you already, I wouldn’t have come if I didn’t think I would win.” Riku staggers, but stays on his feet. He raises his weapon again, his body crying out against the exertion.

“Let’s see what you have left, then.”

They clash once more. Riku knows he can’t keep doing this -- has told himself over and over that a battle of endurance won’t end well for him, and there’s too much riding on the outcome of this battle. Everyone is relying on him. He can’t lose. He _can’t_.

Their Keyblades clang against each other. Riku shoves hard, breaking the gridlock, glaring directly into golden eyes that are as exhausted as his. Abruptly, he remembers the very last tool at his disposal -- the light. _His_ light.

_Consume the darkness, return it to light._

But his grasp on the darkness is slipping, and he’s exhausted. He’s relied on it too much this entire time -- his heart is at its limit. The light is all he has left, but he can’t get to it. Going to the other extreme, trying to reach it now from this deep abyss might end him, but not reaching out to it will spell out certain doom all the same.

Riku swings down at Xehanort, who barely dodges out of the way. Neither of them can continue for much longer. He needs to end this, and fast. But… _how?_

With what little energy he has left in it, Riku tries to call out with his heart. _Sora… Kairi…  I need your help. Please, lend me strength._

_Strength… to protect what matters._

The light is within his grasp, and he locks himself around it, becomes enveloped in it. His Keyblade sears brightly, a beacon in this darkness, a star of hope in this void of despair, and Riku knows that it’s now or never.

Xehanort grunts, shielding his eyes from the radiance coming off of Riku in waves.

“This is it, Xehanort!” The adrenaline makes his head spin, but Riku staves off the feeling the best he can as he lifts his Keyblade, dashing towards Xehanort. Sakura petals drift at the edges of his vision. “ _Let Terra go!_ ” He lunges forward with all the energy, all the strength he has left, to deal what he desperately hopes is the finishing blow.

There’s the sound of scraping metal. Riku’s feet meet the pillar on the opposite side of Xehanort. He immediately collapses to his hand and knees, his chest heaving.

_This is the end._

Xehanort’s Keyblade clatters onto the pillar as he lets out a scream of pain. It subsides, and Riku hears the dull thud of Xehanort’s body toppling over. He breathes out a sigh of sheer relief.

_Finally, it’s over._

Everything goes white.

When Riku opens his eyes, it feels like a weight’s been lifted off of his chest. The darkness is gone -- now uncovered, a beautiful stained glass design sprawls beneath Riku’s knees. It glitters the color of sunset, the color of the earth, and a depiction of Terra stretches across the length of it.

A groan comes from behind him. Riku forces himself to stand and turn around to face the source of the noise.

The man in front of him is flat against the pillar, face-down, but he slowly begins to right himself as he regains consciousness. His movements are incredibly deliberate, borderline jerky, as if he hasn’t moved his own muscles in a long while. He lifts a head of flowing brown locks, and his tired blue gaze locks with Riku’s.

“Terra,” Riku greets, holding out his hand. “Boy, am I glad to see you.”

Terra laughs, voice just as smooth and rumbling as Riku remembers it, and clasps the other’s hand in his own, allowing himself to be pulled up. “Thank you.”

There’s the sound of chimes tinkling and bells ringing, and a Keyhole appears before them. “That’s our door out,” Riku offers helpfully, and Terra nods, back straightening.

Riku raises his Keyblade, pointing it at the Keyhole, but Terra’s voice brings him pause. He turns to look at him, carefully taking in his words.

Terra clenches a hand over his heart, avoiding Riku’s gaze. “The darkness has held me for so long… how can I face them? Am I even still worthy of the Keyblade?”

Riku figures he may just be thinking aloud, that he may not be looking for a response or maybe even hoping that he wouldn’t be heard, but Riku’s been down that path before, and he knows exactly how it feels, and he knows exactly what he needs to say.

He turns to face Terra fully, flipping his Keyblade around and offering him the hilt. “In your hand, take this key. So long as you have the makings, then through this simple act of taking, its wielder you shall one day be.” His voice is soft as he continues, taking in Terra’s stunned expression. “And you will find me, friend -- no ocean will contain you then. No more borders around, or below, or above, so long as you champion the ones you love.”

Terra laughs, eyes stinging as tears begin to streak down his cheeks. He takes Riku’s Keyblade in hand, smiling. “You still remember that, huh?”

Riku nods. “Of course I do. And I still haven’t told anyone.”

Terra wipes his eyes and his face, then reaches out to ruffle Riku’s hair. Riku playfully pushes the offending hand away, laughing. Terra grins back, his shoulders slumping as he finally relaxes. “Thank you.”

Riku nods, raising his weapon to the Keyhole again. “Ready?”

Terra nods in return. “Yeah.”

Riku focuses his attention back on the Keyhole, and his Keyblade begins to sparkle, a bright beam of light shooting from the tip and into the Keyhole. It explodes into light, enveloping the both of them in its warmth.

When the light fades, he and Terra are back in the real world, and back at everyone’s side.

Aqua and Ventus immediately rush over to Terra, their thank yous hasty as their focus hones in on the friend they’ve missed for so long, the missing piece of their trio. Riku doesn’t mind, instead seeking out Sora and Kairi.

He doesn’t find them, per se, but they’re in front of him in the blink of an eye anyway. Mickey’s there too, and Riku can see all their bright smiles and see their lips moving, but his ears are ringing. All the adrenaline, all the energy he dedicated to staying on his feet, all the drive that pushed him to victory, all of it leaves his body in one fell swoop. Riku nods and manages a smile, then his eyes close and he falls unconscious where he stands.

When Riku awakens, he’s aware enough to realize that he’s on a bed, and he figures he’s been taken back to Master Yen Sid’s tower. He opens his eyes and blinks blearily, trying to sit up; he immediately flops back onto the bed as pain wracks his still-exhausted body. He heaves a sigh and relaxes into the mattress, trying his best to relieve himself of the ache.

God, what he wouldn’t give for some water, an Elixir, and a good, _long_ while of bedrest.

He manages to tilt his head enough to keep an eye on the closed door. It’s not long before it opens, but to his surprise, it’s Terra that walks in. Riku thanks his lucky stars that he happens to have a glass of ice water in his hand.

Terra looks just as surprised to see him as he is. “You’re awake.” He perches on the edge of the chair that’s placed next to the bed, setting the glass of water down on the dresser. “Need some help sitting up?”

Riku nods as much as he can. “Please.”

It’s slow-going with the pain that constantly ravages Riku’s body, but in due time, Terra’s got him propped up against a myriad of pillows. He relaxes back into them, closing his eyes briefly and taking a deep breath. “Thanks.”

Terra shakes his head, picking up the glass of water. “No, thank _you_ .” He helps Riku drink it slowly as he speaks. “You saved me, freed my heart from Xehanort’s grip. _Thank you_. I can’t say it enough.”

“It’s the least I could do. I know what it’s like -- Xehanort possessed me, too. But to be trapped in his hold for over a decade…” Riku shudders at the thought. “I don’t know how you did it.”

Terra holds a hand over his heart, sounding incredibly exhausted, though happy at the same time. “It wasn’t easy. But I made it through, and now I’m free.”

At that moment, the door opens again, and Sora and Kairi peek their heads in, seemingly expecting the worst -- however, their expressions light up with the brightness of a million stars at the sight of their best friend up and awake.

Sora is the one who provides the much-needed Elixir -- sheepishly says that Mickey said to wait until he was awake to give it to him -- and the worst of the pain is lifted. Riku’s regained some of his mobility, and with that, he holds his arms out. Kairi’s the first one to leap into his embrace, with Sora not far behind, and this -- this is the reunion they deserve.

The four of them chat for a while, eventually joined by Aqua and Mickey, among others. By the time everyone leaves, it’s late, but Riku feels a million times better than he did when he woke up. He stares out the window, a meteor shower dancing in the reflection of his eyes, and he breathes out a sigh of relief.

Xehanort is finally, finally gone. They won.

**Author's Note:**

> The commands I see Riku specifically using (aside from basic attacks) are Firaga, of course, Fission Firaga, a variation on Dark Maelstrom, and Zantetsuken (my personal favorite). 
> 
> I originally planned for Riku to have a "Philosopher's Stone of one soul" moment and activate a command style or a dream link-type thing, but that didn't pan out -- I'm glad, because writing him struggle with Xehanort's darkness was fun. The parallels to Sora and Aqua are very much so definitely on purpose. I wrangled a bit with the Naminé quotes, but eventually decided what fit best into the rest of the piece. 
> 
> Took 20 days to write and 2 days dedicated solely to editing.
> 
> For the record, I highly doubt this will actually happen in KH3 -- a lot of the elements wouldn't be feasible in gameplay, specifically the dialogue and the whole "double-edged blade darkness" thing. Buuuuut this is still something I enjoyed thinking about and writing out and while I know it probably won't come true, it's nice to dream.


End file.
